Stimulus responsive PNIPAM/QD hybrid microspheres by copolymerization with surface engineered QDs

Abstract

A novel method for effective incorporation of Quantum Dots (QD) into poly(N-isopropylacrylamide) (PNIPAM) polymeric matrix by water-based copolymerization was investigated. The method used was a inverse miniemulsion photopolymerization using a modified sorbitol surfactant Span 80, which provided high quality composite microspheres. QDs were obtained by pyrolysis of the organometallic precursors at high temperature, yielding nanoparticles with hydrophobic ligands coatings. The availability of precisely engineered designer nanocomposites with stimulus responsive polymers is going to support the ultimate integration of QDs in future. A novel, designer polymeric coating for hydrophobic QDs was prepared and used to transfer the QDs from nonpolar to aqueous medium. The analysis has also explored the thermoresponsive PNIPAM/QD assemblies in context with their applications in thermometry, biosensing, temperature modulated bioimaging, and as temperature-controlled drug delivery systems.